Английский язык. Ч.3 (Units 9,10). Ильичева Н.А - 10 стр.

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(10;…)
Interference effects are defined as changes in wave motion produced by
phase and amplitude relations of two or more waves. When two or more waves
have their displacement at all times in the same direction, they reinforce one
another. They are in phase for constructive interference. If their displacements
are in opposite directions, they may cancel each other. Then destructive
interference occurs.
Vocabulary practice
4. Look at the words in bold and try to explain them.
5. Find the words in the text that mean:
1) a kind of natural radiation that makes things visible (1–9);
2) the outer part of an object (2, 3, 4, 5, 6);
3) a completely flat surface (3);
4) not level or smooth (4);
5) a solid figure that is entirely round (i. e. with every point on the surface at
an equal distance from the centre) (5);
6)a line that mark a limit; a dividing line (6);
7) a transparent precious stone of pure carbon in crystallized form, the hardest
substance known (7);
8) a solid geometric figure with a flat base and parallel upright edges (8);
9) a long narrow cut or opening (9).
6. Replace the underlined parts with the equivalent words and phrases from
the text.
1. Only some of the light is
thrown back from the surface which it reaches
.
10
(10;…)
   Interference effects are defined as changes in wave motion produced by
phase and amplitude relations of two or more waves. When two or more waves
have their displacement at all times in the same direction, they reinforce one
another. They are in phase for constructive interference. If their displacements
are in opposite directions, they may cancel each other. Then destructive
interference occurs.


Vocabulary practice


4. Look at the words in bold and try to explain them.


5. Find the words in the text that mean:
  1) a kind of natural radiation that makes things visible (1–9);
  2) the outer part of an object (2, 3, 4, 5, 6);
  3) a completely flat surface (3);
  4) not level or smooth (4);
  5) a solid figure that is entirely round (i. e. with every point on the surface at
    an equal distance from the centre) (5);
  6)a line that mark a limit; a dividing line (6);
  7) a transparent precious stone of pure carbon in crystallized form, the hardest
    substance known (7);
  8) a solid geometric figure with a flat base and parallel upright edges (8);
  9) a long narrow cut or opening (9).


6. Replace the underlined parts with the equivalent words and phrases from
   the text.
  1. Only some of the light is thrown back from the surface which it reaches.


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